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OpenAI发布首个文生视频模型Sora 被引量:1
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《电器》 2024年第3期63-63,共1页
2024年2月16日,OpenAI发布首个文生视频模型Sora。Sora模型可以通过文本描述生成60秒长视频,还可以对视频色彩风格等要素精确理解,创造出人物表情丰富、情感生动的视频内容。据介绍,Sora模型有三大突出亮点,实现了AIGC领域的里程碑式进展。
关键词 文本描述 open 表情丰富 色彩风格 视频 AI 突出亮点
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Artificial Self-Recovery Opens up a New Journey of Autonomous Health of Mechanical Equipments
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作者 Xin Pan Haoyu Zhang +3 位作者 Jinji Gao Weimin Wang Zhinong Jiang Lidong He 《Engineering》 SCIE EI CAS CSCD 2024年第6期22-26,共5页
1.Introduction With the implementation of modern production strategies,such as“Industry 4.0”and“Made in China 2025,”the development of high-end mechanical equipment is gradually reaching a high degree of parameter... 1.Introduction With the implementation of modern production strategies,such as“Industry 4.0”and“Made in China 2025,”the development of high-end mechanical equipment is gradually reaching a high degree of parameterization,digitalization,networking,and intelligence[1].High-end mechanical equipment no longer consists of traditional single devices,but is closely linked to the overall production process;that is,a variety of devices interact with each other and collectively form a complex system.However,faults can lead to production delays throughout the system and even seriously threaten the safety of workers[2].In addition,equipment operating in unmanned air or space vehicles(including space robots)cannot be repaired by humans if they break down[3].Until recently,the typical method of addressing machine faults was primarily the“fault cure”method,which involves manually shutting down,inspecting,and repairing the equipment to restore normal operation.Accordingly,the maintenance cycle of the traditional“fault cure”method is time-consuming,and the quality of the maintenance depends on the skills of the technician[4]. 展开更多
关键词 COLLECTIVE consuming open
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Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries
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作者 Xin Chen Yu Zhang +5 位作者 Chang Chen Huinan Li Yuran Lin Ke Yu Caiyun Nan Chen Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期154-164,共11页
Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult... Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at present.Here,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen battery.On one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox kinetics.On the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic molecules.Therefore,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery. 展开更多
关键词 Atomically dispersed open hollow structure Discharge product LITHIUM Oxygen battery
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Understanding the correlation between energy-state mismatching and open-circuit voltage loss in bulk heterojunction solar cells
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作者 Hyun-Seock Yang Danbi Kim +7 位作者 Chang-Mok Oh Vellaiappillai Tamilavan Pesi MHangoma Hojun Yi Bo RLee Insoo Shin In-Wook Hwang Sung Heum Park 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期164-174,共11页
Photoinduced intermolecular charge transfer(PICT)determines the voltage loss in bulk heterojunction(BHJ)organic photovoltaics(OPVs),and this voltage loss can be minimized by inducing efficient PICT,which requires ener... Photoinduced intermolecular charge transfer(PICT)determines the voltage loss in bulk heterojunction(BHJ)organic photovoltaics(OPVs),and this voltage loss can be minimized by inducing efficient PICT,which requires energy-state matching between the donor and acceptor at the BHJ interfaces.Thus,both geometrically and energetically accessible delocalized state matching at the hot energy level is crucial for achieving efficient PICT.In this study,an effective method for quantifying the hot state matching of OPVs was developed.The degree of energy-state matching between the electron donor and acceptor at BHJ interfaces was quantified using a mismatching factor(MF)calculated from the modified optical density of the BHJ.Furthermore,the correlation between the open-circuit voltage(Voc)of the OPV device and energy-state matching at the BHJ interface was investigated using the calculated MF.The OPVs with small absolute MF values exhibited high Voc values.This result clearly indicates that the energy-state matching between the donor and acceptor is crucial for achieving a high Voc in OPVs.Because the MF indicates the degree of energy-state matching,which is a critical factor for suppressing energy loss,it can be used to estimate the Voc loss in OPVs. 展开更多
关键词 bulk heterojunction open circuit voltage organic photovoltaics photoinduced charge transfer voltage loss
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A comparative study on characteristics of retracted publications across different open access levels
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作者 Er-Te Zheng Hui-Zhen Fu 《Journal of Data and Information Science》 CSCD 2024年第2期22-40,共19页
Purpose:Recently,global science has shown an increasing open trend,however,the characteristics of research integrity of open access(OA)publications have rarely been studied.The aim of this study is to compare the char... Purpose:Recently,global science has shown an increasing open trend,however,the characteristics of research integrity of open access(OA)publications have rarely been studied.The aim of this study is to compare the characteristics of retracted articles across different OA levels and discover whether OA level influences the characteristics of retracted articles.Design/methodology/approach:The research conducted an analysis of 6,005 retracted publications between 2001 and 2020 from the Web of Science and Retraction Watch databases.These publications were categorized based on their OA levels,including Gold OA,Green OA,and non-OA.The study explored retraction rates,time lags and reasons within these categories.Findings:The findings of this research revealed distinct patterns in retraction rates among different OA levels.Publications with Gold OA demonstrated the highest retraction rate,followed by Green OA and non-OA.A comparison of retraction reasons between Gold OA and non-OA categories indicated similar proportions,while Green OA exhibited a higher proportion due to falsification and manipulation issues,along with a lower occurrence of plagiarism and authorship issues.The retraction time lag was shortest for Gold OA,followed by non-OA,and longest for Green OA.The prolonged retraction time for Green OA could be attributed to an atypical distribution of retraction reasons.A comparative study on characteristics of retracted publications across different open access levels Research limitations:There is no exploration of a wider range of OA levels,such as Hybrid OA and Bronze OA.Practical implications:The outcomes of this study suggest the need for increased attention to research integrity within the OA publications.The occurrences offalsification,manipulation,and ethical concerns within Green OA publications warrant attention from the scientific community.Originality/value:This study contributes to the understanding of research integrity in the realm of OA publications,shedding light on retraction patterns and reasons across different OA levels. 展开更多
关键词 open access Retracted publications Reasons for retraction Retraction time lag BIBLIOMETRICS
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Effect of Jianpi Shengxue Tablet on Iron Metabolism and Nutritional Status in Patients with Renal Anemia:A Prospective,Randomized,Open,Parallel Controlled and Multicenter Clinical Study
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作者 Juan YANG Meng-yuan LIANG +15 位作者 Yu LI Hao ZHANG Wei LI Jing LV Li-ping DONG Jing-song JIN Cheng YANG Qing-hong ZHANG Li LONG Rong ZOU Yi GAO Dan SONG Chun-qin PAN Ying YAO Xiao-lin ZHAN Xiao-hui WANG 《Current Medical Science》 SCIE CAS 2024年第3期603-610,共8页
Objective This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia.Methods A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled a... Objective This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia.Methods A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled and randomly divided into two groups.Patients in the control group were treated with polysaccharide-iron complex,and those in the experimental group were administered Jianpi Shengxue tablet.After 8 weeks of continuous treatment,the therapeutic outcomes regarding anemia were compared between the two groups.Results After treatment,the red blood cell(RBC)count,hematocrit(HCT),reticulocyte percentage(RET),ferritin(SF),serum iron(SI),transferrin saturation(TSAT),and serum albumin(ALB)all increased(P<0.01),and the clinical symptom score and total iron binding capacity decreased(P<0.01)in the experimental group.Moreover,the improvements in RBC,HCT,RET,SF,SI,TAST,ALB,and clinical symptoms(fatigue,anorexia,dull skin complexion,numbness of hands and feet)in the experimental group were significantly greater than those in the control group(P<0.05).The total effective rate for treating renal anemia was significantly higher in the experimental group than in the control group(P<0.01).Conclusion The Jianpi Shengxue tablet demonstrates efficacy in treating renal anemia,leading to significant improvements in the laboratory examination results and clinical symptoms of patients with renal anemia. 展开更多
关键词 Jianpi Shengxue tablet renal anemia RANDOMIZED open parallel control multicenter clinical study
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Indications of pro-inflammatory cytokines in laparoscopic and open liver resection for early-stage hepatocellular carcinoma
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作者 Kevin Tak-Pan Ng Li Pang +5 位作者 Jia-Qi Wang Wong Hoi She Simon Hing-Yin Tsang Chung Mau Lo Kwan Man Tan To Cheung 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第3期257-264,共8页
Background:Our clinical practice of laparoscopic liver resection(LLR)had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma(HCC)over open liver resection(OLR),but the underlyi... Background:Our clinical practice of laparoscopic liver resection(LLR)had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma(HCC)over open liver resection(OLR),but the underlying mechanisms are not clear.This study was to find out whether systemic inflammation plays an important role.Methods:A total of 103 patients with early-stage HCC under liver resection were enrolled(LLR group,n=53;OLR group,n=50).The expression of 9 inflammatory cytokines in patients at preoperation,postoperative day 1(POD1)and POD7 was quantified by Luminex Multiplex assay.The relationships of the cytokines and the postoperative outcomes were compared between LLR and OLR.Results:Seven of the circulating cytokines were found to be significantly upregulated on POD1 after LLR or OLR compared to their preoperative levels.Compared to OLR,the POD1 levels of granulocytemacrophage colony-stimulating factor(GM-CSF),interleukin-6(IL-6),IL-8,and monocyte chemoattractant protein-1(MCP-1)in the LLR group were significantly lower.Higher POD1 levels of these cytokines were significantly correlated with longer operative time and higher volume of blood loss during operation.The levels of these cytokines were positively associated with postoperative liver injury,and the length of hospital stay.Importantly,a high level of IL-6 at POD1 was a risk factor for HCC recurrence and poor disease-free survival after liver resection.Conclusions:Significantly lower level of GM-CSF,IL-6,IL-8,and MCP-1 after liver resection represented a milder systemic inflammation which might be an important mechanism to offer better short-term and long-term outcomes in LLR over OLR. 展开更多
关键词 Laparoscopic liver resection open liver resection Hepatocellular carcinoma Postoperative cytokines Inflammatory responses
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Spatial Distribution Feature Extraction Network for Open Set Recognition of Electromagnetic Signal
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作者 Hui Zhang Huaji Zhou +1 位作者 Li Wang Feng Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期279-296,共18页
This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distri... This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distribution feature extraction layer in SDFEN replaces convolutional output neural networks with the spatial distribution features that focus more on inter-sample information by incorporating class center vectors.The designed hybrid loss function considers both intra-class distance and inter-class distance,thereby enhancing the similarity among samples of the same class and increasing the dissimilarity between samples of different classes during training.Consequently,this method allows unknown classes to occupy a larger space in the feature space.This reduces the possibility of overlap with known class samples and makes the boundaries between known and unknown samples more distinct.Additionally,the feature comparator threshold can be used to reject unknown samples.For signal open set recognition,seven methods,including the proposed method,are applied to two kinds of electromagnetic signal data:modulation signal and real-world emitter.The experimental results demonstrate that the proposed method outperforms the other six methods overall in a simulated open environment.Specifically,compared to the state-of-the-art Openmax method,the novel method achieves up to 8.87%and 5.25%higher micro-F-measures,respectively. 展开更多
关键词 Electromagnetic signal recognition deep learning feature extraction open set recognition
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RB-DEM Modeling and Simulation of Non-Persisting Rough Open Joints Based on the IFS-Enhanced Method
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作者 Hangtian Song Xudong Chen +3 位作者 Chun Zhu Qian Yin Wei Wang Qingxiang Meng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期337-359,共23页
When the geological environment of rock masses is disturbed,numerous non-persisting open joints can appear within it.It is crucial to investigate the effect of open joints on the mechanical properties of rock mass.How... When the geological environment of rock masses is disturbed,numerous non-persisting open joints can appear within it.It is crucial to investigate the effect of open joints on the mechanical properties of rock mass.However,it has been challenging to generate realistic open joints in traditional experimental tests and numerical simulations.This paper presents a novel solution to solve the problem.By utilizing the stochastic distribution of joints and an enhanced-fractal interpolation system(IFS)method,rough curves with any orientation can be generated.The Douglas-Peucker algorithm is then applied to simplify these curves by removing unnecessary points while preserving their fundamental shape.Subsequently,open joints are created by connecting points that move to both sides of rough curves based on the aperture distribution.Mesh modeling is performed to construct the final mesh model.Finally,the RB-DEM method is applied to transform the mesh model into a discrete element model containing geometric information about these open joints.Furthermore,this study explores the impacts of rough open joint orientation,aperture,and number on rock fracture mechanics.This method provides a realistic and effective approach for modeling and simulating these non-persisting open joints. 展开更多
关键词 Non-persisting rough open joints stochastic distribution of joints enhanced-IFS method RB-DEM
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Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining
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作者 Jianhua Yan Xiansen Xing +4 位作者 Zhihai Li Weida Ni Liuyuan Zhao Chun Zhu Yuanyuan He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3047-3062,共16页
In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face ... In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities. 展开更多
关键词 open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope
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BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters
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作者 Zhong-Mu Li Cai-Yan Mao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期169-184,共16页
Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each meth... Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess constraint is more appropriate for clusters with small differential reddening, such as globular clusters or older OCs, and clusters that the distances of member stars cannot be determined accurately. 展开更多
关键词 GALAXY stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters
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A highly sensitive fluorescent probe RN-NA reveals peroxynitrite as a novel biomarker for primary open angle glaucoma
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作者 Bo Qin Yuan Lei +3 位作者 Luo Bao You-Jia Zhang Ke-Yin Liu Yu-Hong Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期219-227,共9页
AIM:To directly quantify peroxynitrite(ONOO-)using a highly sensitive fluorescence resonance energy transfer probe RN-NA,investigate the association between ONOOand primary open angle glaucoma(POAG),and clarify whethe... AIM:To directly quantify peroxynitrite(ONOO-)using a highly sensitive fluorescence resonance energy transfer probe RN-NA,investigate the association between ONOOand primary open angle glaucoma(POAG),and clarify whether RN-NA could be used as a potential tool for POAG diagnosis.METHODS:Plasma and aqueous humor(AH)samples were collected from POAG patients(n=100,age:59.70±6.87y)and age-related cataract(ARC)patients(n=100,age:61.15±4.60y)admitted to our hospital.Next,RN-NA was used to detect ONOO-in plasma and AH samples,and the relationship between ONOO-level and POAG was analyzed using binary logistic regression.Besides,Pearson correlation analysis was applied to characterize the correlation of the levels of ONOO-with the patients’age,intraocular pressure(IOP),and mean deviation of visual field testing.The ONOO-scavenger MnTMPyP was employed to treat the 3-morpholinosyndnomine(SIN-1)-induced ocular hypertension in mice(n=7,6-8wk).Finally,the IOP and ONOO-in both eyes were measured 30min after the last drug treatment.RESULTS:ONOO-levels of AH and plasma were significantly higher in the POAG group than in the ARC group(P<0.01).Additionally,ONOO-levels were closely correlated with POAG in a binary logistic regression analysis[odds ratio(OR)=1.008,95%confidence interval(CI):1.002-1.013,P<0.01 for AH;OR=1.004,95%CI:1.002-1.006,P<0.001 for plasma].Pearson correlation analysis showed that ONOO-levels in AH or plasma were positively associated with visual field defects(R=0.51,P<0.01 for AH;R=0.45,P<0.001 for plasma),and ONOO-levels in plasma and AH were correlated in the POAG group(R=0.69,P<0.001).However,administering MnTMPyP to mouse eyes reversed the elevated IOP caused by SIN-1(P<0.05).CONCLUSION:ONOO-levels in AH and plasma,detected by RN-NA,are significantly related to POAG and positively correlated with visual field defects in POAG patients.Hence,ONOO-is a potential biomarker of POAG,especially advanced POAG.Besides,anti-nitration compounds may be novel ocular hypotensive agents based on the animal study. 展开更多
关键词 PEROXYNITRITE fluorescent probe RN-NA primary open angle glaucoma 3-morpholinosyndnomine
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MP-3 microperimeter in early primary open angle glaucoma with a new pattern
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作者 Shuang Liang Li-Tao Wang +2 位作者 Xiao-Li Liu Jia-Liang Duan Dan-Yan Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期861-868,共8页
AIM:To investigate macular microperimetry in patients with early primary open angle glaucoma(POAG)using a new custom-made pattern,and analyze the characteristics of macular sensitivity.METHODS:This case-control study ... AIM:To investigate macular microperimetry in patients with early primary open angle glaucoma(POAG)using a new custom-made pattern,and analyze the characteristics of macular sensitivity.METHODS:This case-control study included 38 patients with POAG,who were divided into pre-perimetric glaucoma(18 eyes of 18 patients),early-stage(20 eyes of 20 patients),and control(20 eyes of 20 patients)groups.All subjects underwent standard 24-2 humphrey visual field test.An MP-3 microperimeter with a new custom-made pattern(28 testing points distributed in four quadrants,covering the central 10°of the retina)was used to evaluate macular sensitivity.Ganglion cell complex(GCC)thicknesses were examined using an RS-3000 Advance OCT system.The features of structure and function were analysed per quadrant.RESULTS:The pre-perimetric glaucoma group had significantly lower inferior hemifield macular sensitivity compared to controls(P<0.05).The early-stage POAG group had significantly lower average,inferior hemifield,inferonasal,and inferotemporal mean sensitivities compared to the pre-perimetric glaucoma group(P<0.05),and lower macular sensitivity in all sectors compared to controls(P<0.05).Regarding GCC thickness,all sectors in the early-stage POAG group became thinner compared to those in controls(P<0.05);whereas all sectors in the early-stage POAG group,except the superonasal quadrant,became thinner compared to those in the pre-perimetric glaucoma group(P<0.05).Macular sensitivity and GCC thickness were significantly associated in each sector.The inferotemporal quadrant had the highest correlation coefficients(0.840).The structure-function relationship for the inferonasal and inferotemporal sectors was stronger compared to the corresponding superior sectors.CONCLUSION:Microperimetry reveals variations in macular sensitivity in patients with early glaucoma earlier than conventional perimetry,particularly in pre-perimetric glaucoma cases in which it might be undetectable by conventional methods.The new custom-made pattern may improve the accuracy of microperimetry by enhancing point arrangement and reducing fatigue effects.Macular sensitivity measured by MP-3 with this pattern shows statistically significant structural and functional associations with the thicknesses of the GCC. 展开更多
关键词 early primary open angle glaucoma macular sensitivity MICROPERIMETRY optical coherence tomography ganglion cell complex
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The Effects of the Geometry of a Current Collector with an Equal Open Ratio on Output Power of a Direct Methanol Fuel Cell
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作者 Yingli Zhu Jiachi Xie +2 位作者 Mingwei Zhu Jun Zhang Miaomiao Li 《Energy Engineering》 EI 2024年第5期1161-1172,共12页
The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too ... The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too little attention has been given to how geometry(including the shape and feature size of the flow field)affects a current collector with an equal open ratio.In this paper,perforated and parallel current collectors with an equal open ratio of 50%and different feature sizes are designed,and the corresponding experimental results are shown to explain the geometry effects on the output power of the DMFC.The results indicate that the optimal feature sizes are between 2 and 2.5 mm for both perforated and parallel flow field in the current collectors with an equal open ratio of 50%.This means that for passive methanol fuel cells,to achieve the highest output power,the optimal feature size of the flow field in both anode and cathode current collectors is between 2 and 2.5 mm under the operating mode of this experiment.The effects of rib and channel position are also investigated,and the results indicate that the optimum pattern depends on the feature sizes of the flow field. 展开更多
关键词 Direct methanol fuel cell GEOMETRY open ratio current collector POSITION
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Clinical effect of laparoscopic radical resection of colorectal cancer based on propensity score matching
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作者 Yang Liu Xian-Xue Wang +3 位作者 Yu-Lin Li Wen-Tao He Hong Li Hua Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期124-133,共10页
BACKGROUND The incidence of colorectal cancer(CRC)is increasing annually.Laparoscopic radical resection of CRC is a minimally invasive procedure preferred in clinical practice.AIM To investigate the clinical effect of... BACKGROUND The incidence of colorectal cancer(CRC)is increasing annually.Laparoscopic radical resection of CRC is a minimally invasive procedure preferred in clinical practice.AIM To investigate the clinical effect of laparoscopic radical resection of CRC on the basis of propensity score matching(PSM).METHODS The clinical data of 100 patients who received inpatient treatment for CRC at Changde Hospital,Xiangya School of Medicine,Central South University(The First People’s Hospital of Changde City)were analyzed retrospectively.The control group included patients who underwent open surgery(n=43),and those who underwent laparoscopic surgery formed the observation group(n=57).The baseline information of both groups was equipoised using 1×1 PSM.Differences in the perioperative parameters,inflammatory response,immune function,degree of pain,and physical status between the groups were analyzed.RESULTS Thirty patients from both groups were successfully matched.After PSM,baseline data showed no statistically significant differences between the groups:(1)Periop-erative parameters:The observation group had a longer surgery time,less intra-operative blood loss,earlier first ambulation and first anal exhaust times,and shorter gastric tube indwelling time than the control group;(2)Inflammatory response:24 h after surgery,the levels of interleukin-6(IL-6),C-reactive protein(CRP),and tumor necrosis factor-α(TNF-α)between groups were higher than preoperatively.IL-6,CRP,and TNF-αlevels in the observation group were lower than in the control group;(3)Immune function:At 24 h after surgery,counts of CD4-positive T-lymphocytes(CD4+)and CD4+/CD8-positive T-lymphocytes(CD8+)in both groups were lower than those before surgery,whereas CD8+was higher than that before surgery.At 24 h after surgery,both CD4+counts and CD4+/CD8+in the observation group were higher than those in the control group,whereas CD8+counts were lower;(4)Degree of pain:The visual analog scale scores in the observation group were lower than those in the control group at 24 and 72 h after surgery;and(5)Physical status:One month after surgery,the Karnofsky performance score in the observation group was higher than that in the control group.CONCLUSION Laparoscopic radical resection of CRC has significant benefits,such as reducing postoperative pain and postoperative inflammatory response,avoiding excessive immune inhibition,and contributing to postoperative recovery. 展开更多
关键词 Colorectal cancer LAPAROSCOPIC open surgery Inflammatory reaction Immune function Propensity score
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Variable Stars in the 50BiN Open Cluster Survey.Ⅲ.NGC 884
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作者 Lin-Hong Wang Qian-Heng Nie +5 位作者 Kun Wang Xiao-Dian Chen Chun-Guang Zhang Li-Cai Deng Xiao-Bin Zhang Tian-Lu Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期36-45,共10页
Open clusters are the basic building blocks that serve as a laboratory for the study of young stellar populations in the Milky Way.Variable stars in open clusters provide a unique way to accurately probe the internal ... Open clusters are the basic building blocks that serve as a laboratory for the study of young stellar populations in the Milky Way.Variable stars in open clusters provide a unique way to accurately probe the internal structure,temporal and dynamical evolutionary stages of individual stars and the host cluster.The most powerful tool for such studies is time-domain photometric observations.This paper follows the route of our previous work,concentrating on a photometric search for variable stars in NGC 884.The target cluster is the companion of NGC869,forming the well-known double cluster system that is gravitationally bound.From the observation run in 2016 November,a total of 9247 B-band CCD images and 8218Ⅴ-band CCD images were obtained.We detected a total of 15 stars with variability in visual brightness,including five Be stars,three eclipsing binaries,and seven of unknown types.Two new variable stars were discovered in this work.We also compared the variable star content of NGC 884 with its companion NGC 869. 展开更多
关键词 STARS variables general-(Galaxy:)open clusters and associations individual(… …)-(stars:)binaries GENERAL
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Impact of open hepatectomy on postoperative bile leakage in patients with biliary tract cancer
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作者 Gang Wu Wen-Ying Li +2 位作者 Yu-Xing Gong Feng Lin Chen Sun 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期67-75,共9页
BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatecto... BACKGROUND Bile leakage is a common and serious complication of open hepatectomy for the treatment of biliary tract cancer.AIM To evaluate the incidence,risk factors,and management of bile leakage after open hepatectomy in patients with biliary tract cancer.METHODS We retrospectively analyzed 120 patients who underwent open hepatectomy for biliary tract cancer from February 2018 to February 2023.Bile leak was defined as bile drainage from the surgical site or drain or the presence of a biloma on imaging.The incidence,severity,timing,location,and treatment of the bile leaks were recorded.The risk factors for bile leakage were analyzed using univariate and multivariate logistic regression analyses.RESULTS The incidence of bile leak was 16.7%(20/120),and most cases were grade A(75%,15/20)according to the International Study Group of Liver Surgery classification.The median time of onset was 5 d(range,1-14 d),and the median duration was 7 d(range,2-28 d).The most common location of bile leakage was the cut surface of the liver(70%,14/20),followed by the anastomosis site(25%,5/20)and the cystic duct stump(5%,1/20).Most bile leaks were treated conservatively with drainage,antibiotics,and nutritional support(85%,17/20),whereas some required endoscopic retrograde cholangiopancreatography with stenting(10%,2/20)or percutaneous transhepatic cholangiography with drainage(5%,1/20).Risk factors for bile leakage include male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion.CONCLUSION Bile leakage is a frequent complication of open hepatectomy for biliary tract cancer.However,most cases are mild and can be conservatively managed.Male sex,hepatocellular carcinoma,major hepatectomy,blood loss,and blood transfusion were associated with an increased risk of bile leak. 展开更多
关键词 open hepatectomy Bile leak Biliary tract cancer Risk factors Management COMPLICATION
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Study of 26 Galactic Open Clusters with Extended Main-sequence Turnoffs
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作者 Yang-Yang Deng Zhong-Mu Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期28-37,共10页
Recent studies indicate that some Galactic open clusters(OCs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs).However,the number of Galactic OCs with eMSTO structures detected so f... Recent studies indicate that some Galactic open clusters(OCs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs).However,the number of Galactic OCs with eMSTO structures detected so far is limited,and the reasons for their formation are still unclear.This work identifies 26 Galactic OCs with undiscovered eMSTOs and investigates the causes of these features.Stellar population types and fundamental parameters of cluster samples are acquired using CMD fitting methods.Among them,the results of 11 OCs are reliable as the observed CMDs are well-reproduced.We propose the crucial role of stellar binarity and confirm the importance of stellar rotation in reproducing eMSTO morphologies.The results also show that the impact of age spread is important,as it can adequately explain the structure of young OCs and fit the observed CMDs of intermediate-age OCs better. 展开更多
关键词 (stars:)binaries:general Galaxy:fundamental parameters (Galaxy:)open clusters and associations:general (stars:)Hertzsprung Russell and C-M-diagrams
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Outcomes of early versus late irrigation and debridement of pediatric open long bone fractures
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作者 Riya Savla Yen-Hong Kuo Nasim Ahmed 《World Journal of Orthopedics》 2024年第6期539-546,共8页
BACKGROUND Open long bone fractures are a major concern for pediatric patients due to the risk of surgical site infection(SSI).Early studies have recommended irrigation and debridement of open fractures within 6 hours... BACKGROUND Open long bone fractures are a major concern for pediatric patients due to the risk of surgical site infection(SSI).Early studies have recommended irrigation and debridement of open fractures within 6 hours-8 hours for the prevention of SSI.According to the American College of Surgeons(ACS)Best Practice Guidelines,in 2015,irrigation and debridement should be done within 24 hours.AIM To identify whether early irrigation and debridement,within 8 hours,vs late,between 8 hours and 24 hours,for pediatric open long bone fractures impacts rate of SSI.METHODS Using retrospective data review from the National Trauma Data Bank,Trauma Quality Improvement Project(TQIP)of 2019.TQIP database is own by the ACS and it is the largest database for trauma quality program in the world.Propensity matching analysis was performed for the study.RESULTS There were 390 pediatric patients with open long bone fractures who were incl-uded in the study.After completing propensity score matching,we had 176 patients in each category,irrigation and debridement within 8 hours and irrigation and debridement between 8 hours and 24 hours.We found no significant differences between each group for the rate of deep SSI which was 0.6%for patients who received surgical irrigation and debridement within 8 hours and 1.1%for those who received it after 8 hours[adjusted odd ratio(AOR):0.5,95%CI:0.268-30.909,P>0.99].For the secondary outcomes studied,in terms of length of hospital stay,patients who received irrigation and debridement within 8 hours stayed for an average of 3.5 days,and those who received it after 8 hours stayed for an average of 3 days,with no significant difference found,and there were also no sig-nificant differences found between the discharge dispositions of the patients.CONCLUSION Our findings support the recommendation for managing open long bone fractures from the ACS:Complete surgical irrigation and debridement within 24 hours. 展开更多
关键词 Pediatric trauma open tibia fracture Irrigation and debridement Timing of intervention Surgical site infection
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《Global Geology》入驻SciOpen平台
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作者 张颖 《世界地质》 CAS 2024年第2期227-227,共1页
SciOpen平台是在中国科技期刊卓越行动计划支持下,由清华大学出版社自主开发的科技期刊国际化数字出版平台。该平台支持科技期刊的全链条数字化生产、管理、发布、运营、推广和移动端服务,与Crossref、STM、COPE等全球主流出版标准化组... SciOpen平台是在中国科技期刊卓越行动计划支持下,由清华大学出版社自主开发的科技期刊国际化数字出版平台。该平台支持科技期刊的全链条数字化生产、管理、发布、运营、推广和移动端服务,与Crossref、STM、COPE等全球主流出版标准化组织建立数字化连接,全面融入全球学术出版体系。 展开更多
关键词 清华大学出版社 学术出版 标准化组织 中国科技期刊 数字出版平台 数字化生产 open
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